Removed the unsetting of ${libPortAudioCpp}
Removed the unsetting of ${libPortAudioCpp}

I was trying to use your cmake-file for one of my projects, though it didn't find the cpp-library correctly. Took a quick peek in the file and found that the variable was unset quickly after it was set and just before it was used. This pull request corrects this.
Hyrtwol/RakNet,laiqiqi886/RakNet,jaynus/RakNet,OculusVR/RakNet,davedissian/dawnengine-RakNet,egildon/RakNet,spencercw/RakNet,laiqiqi886/RakNet,spencercw/RakNet,Vandeer/RakNet,jaynus/RakNet,nestle1998/RakNet,bottompawn/RakNet,xunmengfeng/RakNet,nq-ebaratte/RakNet,xunmengfeng/RakNet,xunmengfeng/RakNet,Vandeer/RakNet,tiantian20007/RakNet,larku/RakNet,davedissian/dawnengine-RakNet,xunmengfeng/RakNet,Vandeer/RakNet,nestle1998/RakNet,nq-ebaratte/RakNet,davedissian/dawnengine-RakNet,Psybrus/RakNet,dasjack/RakNet,egildon/RakNet,fire/LumenNet,tiantian20007/RakNet,larku/RakNet,bottompawn/RakNet,nestle1998/RakNet,laiqiqi886/RakNet,jaynus/RakNet,fire/RakNet,laiqiqi886/RakNet,fire/RakNet,Psybrus/RakNet,Hyrtwol/RakNet,bottompawn/RakNet,nq-ebaratte/RakNet,Hyrtwol/RakNet,OculusVR/RakNet,tiantian20007/RakNet,bottompawn/RakNet,tamtam-im/RakNet,dasjack/RakNet,bottompawn/RakNet,tamtam-im/RakNet,xunmengfeng/RakNet,Hyrtwol/RakNet,Psybrus/RakNet,Hyrtwol/RakNet,png85/RakNet,fire/LumenNet,Vandeer/RakNet,fire/RakNet,fire/LumenNet,jaynus/RakNet,png85/RakNet,nestle1998/RakNet,larku/RakNet,png85/RakNet,OculusVR/RakNet,tiantian20007/RakNet,spencercw/RakNet,OculusVR/RakNet,bottompawn/RakNet,nq-ebaratte/RakNet,nq-ebaratte/RakNet,dasjack/RakNet,larku/RakNet,xunmengfeng/RakNet,Vandeer/RakNet,egildon/RakNet,tamtam-im/RakNet,OculusVR/RakNet,tamtam-im/RakNet,tamtam-im/RakNet,bottompawn/RakNet,Vandeer/RakNet,jaynus/RakNet,davedissian/dawnengine-RakNet,fire/RakNet,dasjack/RakNet,spencercw/RakNet,fire/LumenNet,nestle1998/RakNet,nq-ebaratte/RakNet,png85/RakNet,png85/RakNet,larku/RakNet,Vandeer/RakNet,dasjack/RakNet,egildon/RakNet,Psybrus/RakNet,laiqiqi886/RakNet,tiantian20007/RakNet,Vandeer/RakNet,tiantian20007/RakNet,xunmengfeng/RakNet,larku/RakNet,jaynus/RakNet,Psybrus/RakNet,Psybrus/RakNet,davedissian/dawnengine-RakNet,xunmengfeng/RakNet,davedissian/dawnengine-RakNet,png85/RakNet,fire/RakNet,tiantian20007/RakNet,Psybrus/RakNet,egildon/RakNet,egildon/RakNet,nq-ebaratte/RakNet,png85/RakNet,nq-ebaratte/RakNet,Psybrus/RakNet,larku/RakNet,fire/LumenNet,jaynus/RakNet,larku/RakNet,OculusVR/RakNet,OculusVR/RakNet,tiantian20007/RakNet,png85/RakNet,nestle1998/RakNet,dasjack/RakNet,spencercw/RakNet,larku/RakNet,fire/LumenNet,nestle1998/RakNet,egildon/RakNet,davedissian/dawnengine-RakNet,tamtam-im/RakNet,spencercw/RakNet,jaynus/RakNet,dasjack/RakNet,laiqiqi886/RakNet,Psybrus/RakNet,xunmengfeng/RakNet,tamtam-im/RakNet,tamtam-im/RakNet,egildon/RakNet,bottompawn/RakNet,laiqiqi886/RakNet,Hyrtwol/RakNet,nq-ebaratte/RakNet,nestle1998/RakNet,davedissian/dawnengine-RakNet,fire/LumenNet,Hyrtwol/RakNet,fire/RakNet,bottompawn/RakNet,png85/RakNet,spencercw/RakNet,tiantian20007/RakNet,OculusVR/RakNet,tamtam-im/RakNet,OculusVR/RakNet,jaynus/RakNet,fire/RakNet,spencercw/RakNet,laiqiqi886/RakNet,dasjack/RakNet,spencercw/RakNet,fire/LumenNet,nestle1998/RakNet,egildon/RakNet,fire/RakNet,Vandeer/RakNet,Hyrtwol/RakNet,laiqiqi886/RakNet,Hyrtwol/RakNet,dasjack/RakNet,davedissian/dawnengine-RakNet